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Extension (%) 10 8 6 4 Swell Temperature 19 2 Polythiophene Polymer Gel +0.8V/-0.5V Square Wave 0 18 0 400 800 1200 1600 Time (min) Figure 4. Swell response of polythiophene gel as a function of time for a 20 minute period, +0.8/-0.5V applied square wave potential. Hysteresis in expansion and contraction is evident from the progressive increase in the swell with increasing time. Perturbations in the swell response correlate with small changes in the ambient cell temperature. Figure 5 shows the 300-400 minute portion of this test in greater detail. Figure 5a shows both the axial extension as well as the applied voltage waveform. It is clear from this figure that, within each oxidation pulse, the axial extension was not linear with time. Rather, it fell monotonically with increasing pulse time. It can also be seen that the extension of the specimen did not commence instantaneously upon the onset of the oxidation pulse. Instead, there was an approximately 90 sec lag time before the specimen begins to swell axially. Figure 5b shows the current generated in the cell over the same time period. The current waveform was quite re<strong>prod</strong>ucible, peaking at ≈8 mA at the onset of the reduction pulse and gradually approaching a minimum value of ≈-2 mA early in the oxidation pulse. We note that unlike the extension, the current switched instantaneously with the applied voltage waveform. - 12 - 22 21 20 Temperature (C)
Extension (%) Current (mA) 8 7 6 5 4 10 5 0 -5 Extension Potential Polythiophene Polymer Gel +0.8V/-0.5V Square Wave Current Potential b -10 -1 300 320 340 360 380 400 Time (min) Figure 5. a) Detail view of swell and cell current vs time for a portion of the test shown in Figure 4. b) Current response of the cell for the applied square wave potential. - 13 - a 4 3 2 1 0 4 3 2 1 0 -1 Applied Potential (V) Applied Potential (V)
Page 1 and 2: SANDIA REPORT SAND2001-8166 Unlimit
Page 3 and 4: SAND2001-8166 Unlimited Release Pri
Page 5 and 6: TABLE OF CONTENTS I. INTRODUCTION..
Page 7 and 8: DIRECT MEASURMENT OF EXTENSION AND
Page 9 and 10: The gels were prepared as in the li
Page 11: Growth Direction Figure 3. Morpholo
Page 15 and 16: Pressure (kPa) 25 20 15 10 5 Pressu
Page 17 and 18: DISTRIBUTION 1 US Navy, NAWCWD Rese

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